ISS spots Dragon as commercial craft prepares to dock

With solar panels deployed, Dragon flies over the Indian Ocean beneath the ISS (Image: NASA)

It's so far, so good, for the SpaceX Dragon mission, which is aiming to prove that the world's first privately built rocket and recoverable space capsule can supply the International Space Station. The Dragon capsule successfully reached the ISS today and flew beneath it at a range of 1.6 kilometres before firing its engines to prepare for tomorrow's docking manoeuvres.

The crew on board the ISS had to wait a little longer than expected to catch a glimpse of Dragon: NASA flight directors and the crew undertook extended discussions on how to program the station's TV cameras to find Dragon in the inky void. Shortly after 11.59 am BST, though, the spaceship came into the ISS's view. The view was a little fuzzy, but what matters is that Dragon is there.

ISS astronaut Don Pettit, working in the station's "cupola" viewing
dome, then activated what SpaceX calls the "cuckoo" - the COTS UHF communication unit (CUCU). This radio system - lofted to the ISS by the shuttle Atlantis in 2009
- is a key communications relay between SpaceX, Dragon and the ISS, and
also allows the ISS astronauts to remotely control Dragon. CUCU's first
task was to relay a signal from SpaceX mission control in Hawthorne,
California, to activate a flashing navigation light - and it did indeed
turn on as ordered, telemetry showed. The exercise provided a good indication that the ISS-to-Dragon link is working.